To examine the dissemination of Shiga-toxigenic Escherichia coli (STEC) within cattle groups, dairy calves on two farms utilizing different calf-rearing practices were exposed to a traceable STEC strain. Test strain dissemination differed significantly between farms, with a higher prevalence being associated with group penning. Pen floors and calf hides may be the main environmental mechanisms ...

This study was conducted to determine the effect of experimentally increased glucose demand on voluntary consumption of molasses by dairy calves. Three-week-old calves received 0.365 g of phlorizin by s.c. injection. Urinary output and molasses consumption were measured hourly, and urinary glucose concentration was screened. Molasses consumption for the 24 h after treatment was (mean +/- SE) 72...

Cryptosporidiosis continues to be a problem for dairy calves and a perplexing public health risk, despite recent advances in molecular biology that have contributed to our knowledge of the pathobiology of the causative organism. Cryptosporidium infects at least 155 mammals, including humans and dairy cattle, primarily resulting in diarrhea. Unfortunately, the somewhat unique lifecycle of this p...

In this study we used field data collected from October 2001 to January 2002 to estimate number of days of faecal excretion of Salmonella Dublin bacteria and time to seroconversion in infected calves below the age of 180 days. Based on these estimates all calves in four endemically infected dairy herds were grouped into the following infection states: susceptible (S), infectious (I) and resista...

Over a period of two years, growth rate and health were measured for dairy calves allowed to suckle their mothers up to 6-8 weeks of age. Thirty-one calves were weighted weekly, and the mean daily growth rate was 1.2 +/- 0.03 kg from birth up to 13 weeks of age. Illness in calves and young stock was not observed. In the cows, the mean incidences of ketosis, displaced abomasum, puerperal paresis...

The prevalence of Cryptosporidium species in 1-2-year-old heifers was determined for 571 animals on 14 dairy farms in seven states on the East Coast of the United States. A fecal specimen collected directly from each heifer was processed to concentrate oocysts that were then examined by polymerase chain reaction (PCR). For every PCR-positive specimen the 18S rRNA gene of Cryptosporidium was seq...

This experiment was carried out to study the effect of the inclusion of a yeast culture in the diet of feeder dairy calves on their growth and carcass characteristics. Thirty male Friesian calves were randomly allocated to two groups of 15 each (treatment and control). The calves were fed a total mixed ration for a period of 294 days and then slaughtered to obtain carcass measurements. The yeas...

In recent years, an increasing number of farmers are choosing to keep their cows indoors throughout the year. Indoor housing of cows allows farmers to provide high-yielding individuals with a nutritionally balanced diet fit for their needs, and it has important welfare benefits for both cows and their calves, such as protection from predators, parasites, and exposure to extreme weather conditio...

Human campylobacteriosis is primarily associated with poultry but also cattle. In this study, 55 Campylobacter jejuni strains isolated from 382 dairy calves' feces were differentiated by multilocus sequence typing and tested for antimicrobial resistance. The most prevalent sequence type (ST) was ST883 (20.0%), followed by ST48 (14.5%), and ST50 (9.1%). In contrast to ST48 and ST50, ST883 has ra...